Various problems can arise when organizations having different communications systems must communicate with each other. The need to communication can arise, for example, when multiple first response agencies are required to respond to most major emergencies, for example emergencies that require police departments, fire departments, and emergency medical service personnel. Another example is for large scale, prolonged disaster relief, which may involve military units, federal (e.g., FEMA) and state agencies, as well non-governmental relief organizations such as the Red Cross whose efforts can or advantageously should be coordinated. Many first response and support agencies have independent and incompatible communications systems.
One alternative is to equip all responders with multiple radio systems, so that each organization has a system that will communicate with another organization's system. However, in field conditions this can be impractical, and the cost of procuring, maintaining and even operating multiple systems can be expensive. Another alternative is to equip all responders with the same system. However, this may require most agencies to acquire new radios, which can be expensive, and may fail to address the different needs of the different agencies (security, capabilities, etc.) or may require a prohibitively expensive or complex system in order to satisfy requirements of all the agencies. In addition, using one system may result in insufficient spectrum in large municipalities. Yet a third alternative is to equip all responders or agencies with newly designed, frequency/mode agile radios. However, this may require development of new radios, would require replacement of all radios, and may require extensive training on the part of agencies using the new radios, all of which promise to be expensive. A fourth alternative is to select a small capacity switching system, for example with less than fifty talk paths (which would allow twenty-five separate, simultaneous conversations). However, such systems would likely be inadequate except in small emergencies because talk paths would be overloaded with multiple users trying to have separate conversations. Accordingly, a need exists for a comprehensive, scalable, cost-effective and flexible solution.
An exemplary method for interlinking disparate communication systems includes receiving communications from the disparate communication systems at a center including for each system at least one radio configured to communicate with the system, selectively interconnecting the audio outputs and audio inputs of the radios to interconnect the disparate communication systems, and applying at least one squelch filter to the audio outputs to filter the audio outputs, wherein the interconnecting is based on at least one of a filtered output, a hierarchy of the disparate communication systems, and a command input by a human operator.